# why does the equation x^2=-9 has no real solution why does the equation x^2 = 9 has two solutions

56,329 questions, page 364
1. ## math

A study was conducted to investigate the relationship between the resale price, y (in hundreds of dollars), and the age, x (in years), of midsize luxury American automobiles. The equation of the line of best fit was determined below. yhat = 183.8 −

asked by gayle on May 26, 2013
2. ## precalculus

Berry is standing at the edge of a hill that slopes downward and to the right. He notices that for every 5 feet you go in a horizontal direction, the hill drops by 2 feet. Berry places a ball at the edge of the hill (the origin of the coordinate system),

asked by Anonymous on June 10, 2013
3. ## Calculus

Can someone check my work and answer? Evaluate the integral from -1 to 0 of (4x^6+2x)^3(12x^5+1)dx My work: let u=4x^6+2x dx=du/24x^5+2 now we have the integral from -1 to 0 of u^3(12x^5+1)(du/24x^5+2) Simplifies to the integral from -1 to 0 of

asked by Liz on February 18, 2018

My questions is this: Directions :create one statement in english representing an algebraic representation. I have this: SIMPLE PROBLEM: A DOZEN EQQS COST $1.20. WHAT IS THE PRICE OF EACH (1) EGG. ALGEBRAIC REPRESENTATION OF THIS PROBLEM, QUESTION IS asked by jasmine20 on January 4, 2007 5. ## math A study was conducted to investigate the relationship between the resale price, y (in hundreds of dollars), and the age, x (in years), of midsize luxury American automobiles. The equation of the line of best fit was determined below. yhat = 183.8 − asked by gayle on May 26, 2013 6. ## FINANCE Pls explain and prodive a resource to fine equation. Computing interest tax savings.Dharma Supply has earnings before interest and taxes (EBIT) of$500,000, interest expenses of $300,000, and faces a corporate tax rate of 35%. a. What is Dharma Supply’s asked by CHASE on April 5, 2013 7. ## maths The relationship between the vertical height and the horizontal distance of a ball thrown at 45 degree is given by the equation y = x - x^2/50, where y is the vertical height and x is the horizontal distance. (a) Find the maximum vertical height reached. asked by Shane on September 1, 2013 8. ## Chemistry ---This was the previous one--- Substances A, B, and C can all act as oxidizing agents. In solution, A is green, B is yellow, and C is red. In the reactions in which they participate, they are reduced to A-, B-, and C- ions, all of which are colorless. asked by Gg on October 7, 2014 9. ## Chemistry In the laboratory exercise "Preperation and Properties of Polymers", polyvinyl alcohol is dissolved in water and then reacted with borax (Na2B4O7·10H2O) in water. Which of the following are expected results of this reaction? True or False? 1. Polyvinyl asked by Chem on April 22, 2011 10. ## Chemistry I am very confused on this problem. Any help would be great: 50 g of silver nitrate is mixed with 50 g of hydrochloric acid in a water-based solution. A white precipitate forms (silver chloride.) The solution is filtered and the white precipitate collected asked by Ted on June 23, 2009 11. ## Chemistry A solution contains one or more of the following ions: silver, barium, and Copper (II). CY 105 student adds sodium chloride to a small sample of the solution of the unknown and a white precipitate is formed. He/she filters out the precipitate and then add asked by Allison on March 10, 2015 12. ## chemistry Need help stepping through this for a review. I need to prepare 40grams of a 29% sugar solution. How do I calculate how much sugar and how much water is needed? Was given this formula: weight% (w/w)=100 * (mass of solute/total mass of solution) I set up my asked by j3z on February 3, 2015 13. ## Making a business plan Please check my answer thank you very much Based on the following information below please answer the question that follow. Area A: Brooklyn Brooklyn is a very heavily populated urban area within commuting distance from Manhattan by subway, bus, or car. asked by Mari on March 16, 2009 14. ## Algebra 2 One hundred liters of a 57.84% acid solution is obtained by mixing a 75% solution with a 42% solution. How many liters of each must be used to obtain the desired mixture? A) 40 liters of 75% acid and 60 liters of 42% acid B) 53 liters of 75% acid and 47 asked by Lewis on November 23, 2016 15. ## Algebra 2 One hundred liters of a 57.84% acid solution is obtained by mixing a 75% solution with a 42% solution. How many liters of each must be used to obtain the desired mixture? A) 40 liters of 75% acid and 60 liters of 42% acid B) 53 liters of 75% acid and 47 asked by Lewis on November 23, 2016 16. ## Math The total cost C(q) of producing q goods is given by the following equation. C(q) = 0.01q^3 − 0.6q^2 + 13q a) What is the fixed Cost? b) What is the maximum profit if each item is sold for$9? (Assume you sell everything you produce. Round your answer to

asked by Jenner on December 17, 2015
17. ## chemistry

A sample of water is found to contain 0.059 ppm of Pb2+ ions. Calculate the mass of lead ions per liter of this solution (assume the density of the water solution is 1.0 g/mL) 1.2E-2 g/L Pb2+ 5.9E-8 g/L Pb2+ 5.9E-5 g/L Pb2+ 1.2E-5 g/L Pb2+ 2.9E-10 g/L Pb2+

asked by Heaton on February 5, 2012
18. ## Chemistry (Acid/Base)

Consider a solution made by mixing 100 mL of 2.0 M acetic acid (Ka= 1.8e-5) with 100 mL of 0.00020 M benzoic acid (Ka= 6.4e-5). How many moles of solid NaOH must be added to the solution so that half of the benzoic acid is protonated (i.e. such that [HA] =

asked by Emily on April 9, 2015
19. ## chemistry

A solution contains naphthalene (C10H8) dissolved in hexane (C6H14) at a concentration of 11.39{\rm \\%} naphthalene by mass. Calculate the vapor pressure at 25 ∘C of hexane above the solution. The vapor pressure of pure hexane at 25 ∘C is 151 torr.

asked by kales on February 8, 2015
20. ## Chemistry

An aqueous solution that 2.00 M in AgNO3 is slowly added from a buret to an aqueous solution that is 1.00×10−2 M in Cl− and 0.260 M in I−. When the second ion begins to precipitate, what is the remaining concentration of the first ion? I know that

asked by Sydney on June 5, 2016
21. ## chemistry

In the REDOX reaction in basic solution Zn-->Zn(OH)4+H2 I know that the first half reaction is 4H20+Zn-->Zn(OH)4 +4H+e but the second one is either 2e+2H2O--->H2+2OH (WHICH IS THE ANSWER GIVEN ON THE WORKSHEET) OR 2e+2H-->H2 I think both leads to the same

asked by george on November 4, 2010
22. ## chem

A 27.4 mL sample of an unknown HClO4 solution requires 45.4 mL of 0.101 M NaOH for complete neutralization. What was the concentration of the unknown HClO4 solution? The neutralization reaction is shown below. HClO4(aq) + NaOH(aq) H2O(l) + NaClO4(aq)

asked by BOBBY on March 14, 2011
23. ## chemistry

A solution contains naphthalene (C10H8) dissolved in hexane (C6H14) at a concentration of 11.07 % naphthalene by mass. Calculate the vapor pressure at 25 ∘C of hexane above the solution. The vapor pressure of pure hexane at 25 ∘C is 151 torr.

asked by elizabeth on September 24, 2016
24. ## chemistry

Draw the tritration curve for the neutralization of a 100ml sample of 1M solution of HCl with a .6M solution of Naoh point 1: 2 ml NaOH edded point 2: 40 ml NoOH ADDED POINT 3: EQUIVALENCE POINT 4: 80 ML NaOH added

asked by sam on April 3, 2011
25. ## math

gregor is planning a driving trip where he knows that half his trip will be along major highways and part on country roads. The speed limit is 100km/h on highways and 60km/h on other roads. the total time he wants to spend driving is 12h. I set up the

asked by Calie on June 1, 2008
26. ## Algebra one story problem help please.

in 1993, 2.00 Million females particpaited in U.S Highschool sports, by 2003, the number increased to 2.86 Mill. A) Write an equation in slope-intercept form that gives the number of females participaiting in US. highschool sports, ( in Millions) as a

asked by Allyson on December 9, 2010
27. ## Question

@Alex asked this question when I was on earlier: Let line l_1 be the graph of 5x + 8y = -9. Line l_2 is perpendicular to line l_1 and passes through the point (10,10). If line l_2 is the graph of the equation y=mx +b, then find m+b. I'm wondering like how

asked by Yuuna on September 4, 2017

Given the following information, answer the following: TR=$3Q TC=$1,200 = $2Q 1. what is the break-even level of output? 2. If the firms sells 1,300 units, what are its earnings or losses? 3. If sales rise to 2,000 units, what are the firms earnings or asked by Rald on January 17, 2016 29. ## Calculus What would the values of A, B, and C be in this problem? The tides in a particular bay can be modeled with an equation of the form d= A cos (Bt) + C, where t represents the number of hours since high-tide and d represents the depth of water in the bay. The asked by Jillian on August 22, 2012 30. ## math words problem Rich’s weekly salary is based on the number of pairs of shoes he sells. He is paid a base salary of$25, plus $5 for every pair of shoes he sells. The relationship between his pay (p) and pairs of shoes (s) sold can be represented by the linear equation asked by MICHELLE on December 12, 2013 31. ## calc and Vectors A wire 60 cm long is to be cut into two pieces. One of the pieces will be bent into the shape of a square and the other into the shape of an equilateral triangle. The wire is to be cut in order that the sum of the areas of the square and the triangle is to asked by Annie on January 22, 2014 32. ## Algebra Three years after purchase, a car is estimated to be worth$24,000. At five years, its value is $19,000. If the car is depreciating in a linear manner, write an equation that represents the depreciation of the car. Answer the following questions: a. How asked by Steveo on February 11, 2014 33. ## Finance ****HELP PLEASE**** Given the following information, answer the following: TR=$3Q TC= $1,200 =$2Q 1. what is the break-even level of output? 2. If the firms sells 1,300 units, what are its earnings or losses? 3. If sales rise to 2,000 units, what are the

asked by AJ on January 26, 2016

Given the following information, answer the following: TR=$3Q TC=$1,200 = $2Q 1. what is the break-even level of output? 2. If the firms sells 1,300 units, what are its earnings or losses? 3. If sales rise to 2,000 units, what are the firms earnings or asked by Rald on January 17, 2016 35. ## physics For any circuit the number of independent equations containing emfs, resistances, and currents equals the number of branches. why? The only type of circuit that branches is parallel. But there can be electric circuit with a combination of both parallel and asked by susane on March 15, 2007 36. ## algebra Monigue and Tasha are traveling on the same highway to family reunion at a park. Monique starts out 225 miles from the park and drives 70 miles per hour. Tasha starts out 200 miles from the park and drives 65 per hour. Write an equation for Monique`s where asked by Imaya on November 18, 2014 37. ## Chemistry Pretest Consider the following balanced equation. 2 H2 + O2 ---> 2 H2O Which of the following statements is false? a) One molecule of O2 will react with 2 molecules of H2 b) One mole of O2 will react with 2 moles of H2 c) The complete reaction of 32.0 g of O2 will asked by Sarah on September 28, 2012 38. ## Math An adult polar bear walks at an average rate of 5 kilometers per hour. 1. write an equation to find k, the number of kilometers a polar bear bear can walk in h hours. 2.make a table to show the relationship between the number of kilometers k a polar bear asked by Angelina on February 21, 2015 39. ## Calculus The fuel consumption (gallons per hour) of a car traveling at a speed of v miles per hour is c = f(v). 1) What is the meaning of the derivative f ' (v)? answer: rate of change of fuel consumption as miles go up 2) What are its units? answer: miles per asked by Maia on February 6, 2016 40. ## Math Word Problem Cashews sell for$4.00 per pound and peanuts for $1.50 per pound. The peanuts didn't sell well, so in order to sell 60 lbs of peanuts the manager decided to mix 60 lbs of peanuts w/ cashews and sell the mixture for$2.50 per pound. How many lbs cashews

asked by Amy~ on September 12, 2010
41. ## Math

Imagine that there is a circular track given by the equation x2+y2=2102500, where both x and y are measured in units of feet. At time t=0, Robin is at point (1450,0) and Shannon is at point (−170,1440). Both are running counterclockwise, with Shannon

asked by PLS HELP!! ASAP on April 21, 2016
42. ## chem

a) Co(H2O)6^2 + 4 Cl^‐1 (aq) ⇄ CoCl4^‐2 (aq) + 6 H2O (l) Rewrite the net ionic equation above including the energy term where appropriate. The Delta H for this reaction is +50 kJ/mol. b) Silver chloride (AgCl) is a white solid. For the equilibrium

asked by Victor on October 4, 2015
43. ## Algebra 1

First of all, we're learning how to solve equations with variables on both sides. Write and solve an equation for the situation. An architect is designing a rectangular greenhouse. Along one wall is a 7-ft storage area and 5 sections for different kinds of

asked by Mercedez on November 3, 2011
44. ## algebra

i was wondering if i did this right A cannon ball is shot from a cannon on top of a hill that is 73.5 meters above sea level. The cannon ball leaves the cannon with a velocity of 9.8 m/s. Write and solve a quadratic equation to determine when the cannon

asked by sarah on August 22, 2011
45. ## Trig

Two pullies are connected by a belt, Pulley A has a radius of 3 cm and pulley B has a radius of 6cm. As Pulley A rotates, a drop of paint on the circumference of pulley B rotates around the axle of Pulley B. Initially the paint drop is 7 cm above the

asked by Anonymous on May 17, 2018
46. ## Math

Imagine that there is a circular track given by the equation x2+y2=1123600, where both x and y are measured in units of feet. At time t=0, Robin is at point (1060,0) and Shannon is at point (560,900). Both are running counterclockwise, with Shannon running

47. ## math

McDougal's Restaurant has a play area for children under and around their giant arch ( in the shape of parabola with negative orientation). They plan to set up a new activity that allows children to bungee jump from the arch. The manager, upon hearing of

asked by Anonymous on January 4, 2012
48. ## Math

A delivery service charges a base price for an overnight delivery of a package plus an extra charge for each pound the package weighs. A customer is billed $22.85 for shipping a 3-pound package and$40 for shipping a 10-pound package. 1.) Write an equation

asked by Kiri on August 2, 2012
49. ## math/algebra

I have a triangle one side = 3 side 2 = square root5 - square root 3 side 3 = square root 5 + square root 3 I can get the answer 3 and I know I am missing the square root part of the equation can you help me by showing how this problem is worked so I can

asked by Dee on July 22, 2007
50. ## Calculus 2 (Differentiate & Decay Problem)

I have two problems I need help on, can someone show and explain step by step how to do the problems? For #1, how would you differentiate and solve the inital-value problem? For #2, I don't understand what I am doing wrong with the problem..I am sure it is

asked by Misa on March 29, 2015
51. ## Calculus

I finished this problem but I wanted some feedback because I don't know if it's entirely correct. Suppose that functions f and g and their derivatives with respect to x have the following values at x=2. f(x)=8 g(x)=2 f'(x)=1/3 g'(x)=-3 Find d/dx of f(g(x))

asked by Lauren on April 1, 2009
52. ## Physics

A uniform plank of length 5.5 m and weight 219 N rests horizontally on two supports, with 1.1 m of the plank hanging over the right support (see the drawing). To what distance x can a person who weighs 447 N walk on the overhanging part of the plank before

asked by Mary on March 21, 2007
53. ## Physics

A 25.0 m tall hollow aluminum flagpole is equivalent in strength to a solid cylinder of aluminum 3.50 cm in diameter. A strong wind bends the pole much as a horizontal force of 900 N exerted at the top would. How far to the side does the top of the pole

asked by Jimmy on February 21, 2015

To make the Chinese dish "dragon's beard noodles," fold a 5 ft. strand of dough in half. Stretch the dough back to its original length so that two thinner strands are formed. Repeat this folding and stretching process over and over to produce increasing

asked by Joy on April 18, 2009
55. ## chemisty

Many home barbecues are fueled with propane gas (C3H8). How much carbon dioxide in kilograms is produced upon the complete combustion of 18.9 L of propane (approximate contents of one 5-gal tank)? Assume that the density of the liquid propane in the tank

asked by Carry on March 1, 2007
56. ## physics

I'm making a graph of force vs stretch for springs. I have 7 data trials with the k (F = kx) ranging from 28 to 31, average is 29.6. Now I need to find the slope and write an equation for the graph. If I use the first two points to get the slope, I get a

asked by Kriti on March 17, 2011
57. ## Biotech

The dynamic method is used to measure kLa in a fermentor operated at 30degC. Data for dissolved-oxygen concentration as a function of time during the re-oxygenation step is given (table with time (s) and CAL (% air saturation)). The equilibrium

asked by MGob on October 30, 2012
58. ## Dynamics

A French artillerist, Captain A. Le Duc, developed an empirical formula for the velocity of a projectile in terms of the distance traveled by the projectile in the bore. For a 155-mm gun this equation is v = 3309s /(70 + s) where s is the distance traveled

asked by stan on January 19, 2011

Given A(-4,-2), B(44), and C(18,-8, answer the following questions Write the equations of the line containing the altitude the passes through B in standard form. Write the equation of the line containing the median that passes through point C in

asked by PoPo on January 20, 2017
60. ## Trigonometric Functions

A person is riding a ferris wheel that turns at a constant speeed. The lowest point of the ferris wheel is at ground level. Another person is standing at the side of the wheel on a platform 4m above the ground. She notes the times that the person on the

asked by REALLY URGENT on May 5, 2014
61. ## physics

Water flows through a horizontal tube of diameter 2.7 cm that is joined to a second horizontal tube of diameter 1.9 cm. The pressure difference between the tubes is 7.6 kPa. Find the speed of flow in the first tube. v_1 = ? m/s I've tried using P_1 + .5 *

asked by Trent on December 8, 2011
62. ## Chemistry

A proposed mechanism for a reaction is: (i) A + B2 = AB2 Ea1 = 12 kJ/mol ƒ´H1 = 3 kJ/mol (ii) AB2 + C2 = ABC + BC Ea2 = 30 kJ/mol ƒ´H2 = 5.2 kJ/mol (iii) ABC + B2 = AB2 + BC Ea3 = 10 kJ/mol ƒ´H3 = -7.8 kJ/mol a) Which is the rate determining step?

asked by Sarah on September 20, 2014
63. ## Physics

A sealed container of volume 0.10 m3 holds a sample of 3.0 x 10^24 atoms of helium gas in equilibrium. The distribution of speeds of helium atoms shows a peak at 1100 ms-1. Caluculate the temperature and pressure of the helium gas. (helium atom 4.0 amu)

asked by Oli on May 19, 2008
64. ## Chemistry

Silver chromate is sparingly soluble in aqueous solutions. The Ksp of Ag2CrO4 is 1.12× 10–12. What is the solubility (in mol/L) of silver chromate in 1.4 M potassium chromate aqueous solution? In 1.4 M silver nitrate aqueous solution? In pure water?

asked by Katherine on November 12, 2013
65. ## macroeconomics

The initial Phillips curve relationship implied that the opportunity cost of __________ __________ was higher __________. If high unemployment lasts a long time, it could cause potential real GDP to fall. (true or false)

asked by Amber on December 13, 2009
66. ## Biochemistry

Determine the MAX amount of titrant you will possibly need for your titration. Your unknown solution has been prepared by dissolving btw 0.05-0.09mol of zwitterion form of the amino acid in 1L of ~ 0.1M HCl solution. you will titrate 50mL of that amino

asked by Abba on May 18, 2015
67. ## Biochemistry

Determine the MAX amount of titrant you will possibly need for your titration. Your unknown solution has been prepared by dissolving btw 0.05-0.09mol of zwitterion form of the amino acid in 1L of ~ 0.1M HCl solution. you will titrate 50mL of that amino

asked by Abba on May 19, 2015
68. ## Biochemistry

Determine the MAX amount of titrant you will possibly need for your titration. Your unknown solution has been prepared by dissolving btw 0.05-0.09mol of zwitterion form of the amino acid in 1L of ~ 0.1M HCl solution. you will titrate 50mL of that amino

asked by Abba on May 18, 2015
69. ## pre-calculus 11

The question is the roundtrip flight from Edmonton to Toronto covers a distance of 5400km in 7.6 hours. The speed from Edmonton to Toronto was 95 km/h faster than the speed from Toronto to Edmonton. What was the speed of the plane from Toronto to Edmonton?

asked by george on June 16, 2015
70. ## Managerial Economics

Consider the Linear demand function Q = 20 - 0.5P c- Using calculus, find the level of output, Qrmax, where total revenue reaches its maximum value. What price Prmx maximizes total revenue? What is the value of TR at this maximum point. d- Write the

asked by alejandro guzman on March 12, 2013
71. ## PHYSICS

Three moles of an ideal gas are compressed from 5.5*10^-2 to 2.5*10^-2 m^3. During the compression, 6.1*10^3J of work is done on the gas, and heat is removed to keep the temperature of the gas constant at all times. Find the temperature of the gas. I

asked by sTELLA on March 2, 2008
72. ## Urgent gr11 trig!!!

A tidal wave reaches low tide at 3:00AM and high tide at 3:00PM. The tide can rise and fall 10m from the sea level. If at low tide the water level is 2m above the seabed (bottom of the sea) a) determine an equation to model the sea level above the sea bed

asked by Rose on January 30, 2018
73. ## Chemistry(Please respond, thank you)

For an experiment I had to add 1 drop of 1.0M HCl into a test tube that had 2.5mL of 0.10M Na2CrO4 and record the color. The original color of the Na2CrO4 was yellow. After adding the HCl the color became a very dark yellow. I know that the equilibrium

asked by Hannah on March 20, 2012
74. ## Chemistry: Please check my work!I am stumped

When nitroglycerin (C3H5N3O9) explodes, it decomposes into the following gases: CO2, N2, NO, and H2O. If 239g of nitroglycerin explodes, what volume will the mixture of gaseous produces occupy at 1.00 atm pressure and 2678oC? a. Write a balanced equation

asked by Suzanne on April 28, 2014
75. ## math equation

At east end middle school, twice as many students study spanish as study latin. The spanish class has 3 fewer than 25 Students. LET L REPRESENT THE NUMBER OF STUDENTS IN LATIN CLASS. USE THE GIVEN INFORMATION TO WRITE AN EQUATION TO FIND THE NUMBER OF

asked by sara on April 17, 2009
76. ## Algebra 2

The number of pages p a student can read varies directly with respect to time t in minutes spent reading. The student can read 90 pages in 60 minutes. Write an equation that relates pages read & time. Predict the number of pages in 90 minutes. Answer

asked by Michael on August 24, 2014
77. ## Algebra

The sum of Eric and Bob's weights is 9 times greater than the difference of their weights. The positive difference of their weights is also 240 pounds less than the sum. If Eric weighs less than Bob, find Bob's weight. I am not sure at all how to solve

asked by Rachelle on February 17, 2009
78. ## Calculus AB

Could someone please help me with these tangent line problems? 1) Find the equation of the line tangent to the given curve at the indicated point: 3y^3 + 2x^2 = 5 at a point in the first quadrant where y=1. 2) Show that there is no point on the graph of

asked by Annie on November 25, 2016
79. ## algebra

which method do you use to solve this equation.(x-1)^2=7. Is it the factoring method or the sqare root method I would take the square root of each side. (x-1)= +- sqrt7 Now for the factoring method: (x-1)^2=7 (x-1)^2-7=0 you have a difference of two

asked by Tony on May 17, 2007
80. ## Calculus

During a certain epidemic, the number of people that are infected at any time increases at rate proportional to the number of people that are infected at that time. 1,000 people are infected when the epidemic is first discovered, and 1,200 are infected 7

asked by Anonymous on April 9, 2015
81. ## physics

There is a problem that asks if an ice cube is dropped into nitrogen (boiling point of nitrogen is 77K), how much nitrogen will evaporate? heat lost by ice = heat gained by nitrogen But by is the equation m(ice)*c(ice)*deltaT = m(nitrogen)*L(vaporation) ?

asked by Pegs on April 21, 2011

If a population consists of 10,000 individuals at time t=0 years (P0), and the annual growth rate (excess of births over deaths) is 3% (GR), what will the population be after 1, 15 and 100 years (n)? Calculate the "doubling time" for this growth rate.

asked by Rani on October 6, 2009

Tickets for a concert sold for $11 and$8. If 600 tickets were sold for one evening and the receipts were $5500, how many of each were sold? Let the number of$11 tickets be x, then the number of $8 tickets would be 600-x Now we consider the cost of these asked by vet on July 22, 2007 84. ## CHEMISTRY 4NH3 + 7O2 = 4NO2 + 6H2O HHOW MANY MOLES OF AMMONIA WILL BE REQUIRED TO PRODUCE 10.0 MOLES OF WATER? The equation tells you 4 mols NH3 will produce 6 mols H2O. Can you set up a proportion to make that work? For example, 2 mols NH3 would produce 3 mols H2O asked by Janice on July 17, 2007 85. ## algebra 2. How many pounds of chocolate worth$1.20 a pound must be mixed with 10 pounds of chocolate worth 90 cents a pound to produce a mixture worth \$1.00 a pound? What Do I Know? What Do I Want to Know? Assign Variables Write a verbal Model: How Do I Find the

asked by peg on November 17, 2010
86. ## Science

Geologist believe that The crystals inside a geode probably form when... A: Lava suddenly cools on earth’s surface B: Minerals dissolved in a solution evaporate C: Minerals dissolved in a solution crystallize D: magma cools slowly inside Earth Ok so

87. ## chemistry

An ideal liquid solution has two volatile components. In the vapor in equilibrium with the solution, the mole fractions of the components are (a) both 0.50; (b) equal, but not necessarily 0.50; (c) not very likely to be equal; (d) 1.00 for the solvent and

asked by david on February 20, 2010
88. ## chemistry

A 1 m solution of MgCl2 will cause the decrease in the freezing point of water to be approximately ___ than that caused by a 1 m solution of sucrose a. 3x kleiner/ 3x smaller b. 2x kleiner / 2x smaller c. dieselfde / the same d. 2x groter / 2x greater e.

asked by Megan on August 1, 2010
89. ## Chemistry (URGENT)

Calculate the molarity of the Co^2+ ion in each of the solutions 1-5. The new molarity is given by the molarity of the stock solution multiplied by the dilution factor. Solution: Co(NO3)2 Original molarity: 0.160 Dilution #1: none D#2: 12mL to 16mL D#3:

asked by John on December 15, 2010
90. ## math, help

can someone show me how to do this one i have plenty of them so can you show me step by step when someone gets a chance. Thank you. Solve the system by graphing x+y=3 x+y=-1 What I would do is to put the equations in slope intercept form: y= -x + 3 y= -x

asked by jasmine20 on February 10, 2007
91. ## Chemistry

The standard electrode potentials for zn/zn and cu/cu are -0.76v and 0.34v respectively at 298k.calculate the free energy change when a zinc rod is dip into a zinc tetraoxosulphate(vi) solution and a copper rod is dip into a copper(ii)tetraoxosulphate(vi)

asked by Precious on November 7, 2018
92. ## chem

Determine the mass(w/w%) percent of CaCl2 given the following information. The vapor pressure of a CaCl2 solution is 81.6 mmHg at 50degrees C. The vapor pressure of pure water at this temp is 92.6mmHg. Assume that you have 1.00mol of water.[Raoult's Law:

asked by kale on July 16, 2015
93. ## Pre-Calculus

(not sure how to type square root of) square root of 3x - 4 = (x-4)^2-3 Normally, I either take the square root of both sides or I square both sides. Since one side of the equation is square root of 3x-4 and the other side is (x-4) squared - 3, I am

asked by Ashley on September 6, 2009
94. ## Chem

You have 25.00 mL of 3% by mass solution of hydrogen peroxide. Assume the density of this solution is 1.00 g/mL. If all of the hydrogen peroxide decomposes to water and oxygen according to the reaction below: 2H2O2 (aq) 2H2O (l) + O2 (g) What is the total

asked by Blake on September 21, 2015
95. ## Algebra!

Can someone help me with these problems so i can do the rest of my textbook work on my own plz? What is the value of n so that the expression x^2+11x+n is a perfect square trinomial? (1 point) What is a solution of x^2+6x=-5? (1 point) What is the solution

asked by Gabby on March 24, 2014
96. ## math,correction

can someone correct this for me. Directions: Solve the following systems by using either addition or substitution. If a unique solution does not exist, state whether the system is dependent or inconsistent. 10x + 2y = 7 y = -5x + 3 the answer: The variable

asked by jasmine20 on February 5, 2007
97. ## Math

1.Write the equation 5x+y-2=0 in normal form. 5x+y-2=0 5x+y=2 (add two to both sides) Standard form (Ax+By=C)---> 5x+y=2 Y-intercept (when x equals 0) 5x+y-2=0 5x+y=2 5(0) +y=2 y=2 X-intercept (when y equals 0) 5x+y-2=0 5x+y=2 5x+0=2 x=2/5 Slope intercept

asked by Jon on April 25, 2009
98. ## Chemistry

A galvanic (voltaic) cell consists of an electrode composed of aluminum in a 1.0 M aluminum ion solution and another electrode composed of fold in a 1.0 M gold (III) ion solution connected by a salt bridge. Calculate the standard potential for this cell at

asked by Morgan on October 9, 2012
99. ## AP Chemistry

A solution is prepared by mixing 0.0200 mol CH2Cl2 and 0.0500 mol CH2Br2 at 25°C. Assuming the solution is ideal, calculate the composition of the vapor (in terms of mole fractions) at 25°C. At 25°C, the vapor pressures of pure CH2Cl2 and pure CH2Br2

asked by Sarah on March 22, 2010
100. ## chemistry

The triprotic acid H3A has ionization constants of Ka1 = 9.9× 10–2, Ka2 = 2.7× 10–8, and Ka3 = 5.9× 10–11. a). Calculate the following values for a 0.0570 M solution of NaH2A H+ ?? [H2A^-/H3A]?? b). Calculate the following values for a 0.0570 M

asked by Laura on March 28, 2013